The present invention relates to a radiation cooling unit for cooling dust-laden gases. The unit includes a tank, at least one cylindrical radiation heat transfer surface that is disposed adjacent to, and extends essentially along the length of, the inner wall of the tank, and knock-or impact-beating devices that are disposed externally of the tank and act upon the cylindrical radiation heat transfer surface through the wall of the tank.
The prospectus "Anlagen- und Apparatebau-Komponenten und Teilkreislaufe" P 8604-06-05/1.L (1986) page 27, discloses, for a coal gasification unit in a molten iron bath, a radiation cooler that is disposed downstream of the bath, is provided with a radiation heat transfer surface, and can be cleaned with mechanically or pneumatically operated knocking- or impact-beating devices. the cylindrical radiation heat transfer surface is of tube-web-tube construction, whereby the tubes can extend parallel to the axis of the tank.
The knock- or impact-beating device can be of the type disclosed in U.S. Pat. No. 4,457,361, which belongs to the assignee of the present invention, and where the impact piston, which comes into engagement with the cooling surface, extends through the wall of the pressure tank, with the free end of the impact piston being acted upon by the transfer piston of the pulse generator.
The knock- or impact-beating devices are required because the heretofore known radiation cooler tends to become dirty or clogged due to the presence of the solid constituents in the gas that is to be cooled off. In addition, merely the arrangement of the wall heat transfer surfaces causes the space of the radiation cooler to be poorly utilized.
It is therefore an object of the present invention to provide a radiation cooling unit of the aforementioned general type where the space in the cooling unit can be better utilized, or the cooling unit can have smaller dimensions.